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Su H, Guo H, Qiu X, Lin TY, Qin C, Celio G, Yong P, Senders M, Han X, Bernlohr DA, Chen X. Lipocalin 2 regulates mitochondrial phospholipidome remodeling, dynamics, and function in brown adipose tissue in male mice. Nat Commun 2023; 14:6729. [PMID: 37872178 PMCID: PMC10593768 DOI: 10.1038/s41467-023-42473-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 10/11/2023] [Indexed: 10/25/2023] Open
Abstract
Mitochondrial function is vital for energy metabolism in thermogenic adipocytes. Impaired mitochondrial bioenergetics in brown adipocytes are linked to disrupted thermogenesis and energy balance in obesity and aging. Phospholipid cardiolipin (CL) and phosphatidic acid (PA) jointly regulate mitochondrial membrane architecture and dynamics, with mitochondria-associated endoplasmic reticulum membranes (MAMs) serving as the platform for phospholipid biosynthesis and metabolism. However, little is known about the regulators of MAM phospholipid metabolism and their connection to mitochondrial function. We discover that LCN2 is a PA binding protein recruited to the MAM during inflammation and metabolic stimulation. Lcn2 deficiency disrupts mitochondrial fusion-fission balance and alters the acyl-chain composition of mitochondrial phospholipids in brown adipose tissue (BAT) of male mice. Lcn2 KO male mice exhibit an increase in the levels of CLs containing long-chain polyunsaturated fatty acids (LC-PUFA), a decrease in CLs containing monounsaturated fatty acids, resulting in mitochondrial dysfunction. This dysfunction triggers compensatory activation of peroxisomal function and the biosynthesis of LC-PUFA-containing plasmalogens in BAT. Additionally, Lcn2 deficiency alters PA production, correlating with changes in PA-regulated phospholipid-metabolizing enzymes and the mTOR signaling pathway. In conclusion, LCN2 plays a critical role in the acyl-chain remodeling of phospholipids and mitochondrial bioenergetics by regulating PA production and its function in activating signaling pathways.
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Affiliation(s)
- Hongming Su
- Department of Food Science and Nutrition, University of Minnesota-Twin Cities, St. Paul, MN, 55108, USA
| | - Hong Guo
- Department of Food Science and Nutrition, University of Minnesota-Twin Cities, St. Paul, MN, 55108, USA
| | - Xiaoxue Qiu
- Department of Food Science and Nutrition, University of Minnesota-Twin Cities, St. Paul, MN, 55108, USA
| | - Te-Yueh Lin
- Department of Food Science and Nutrition, University of Minnesota-Twin Cities, St. Paul, MN, 55108, USA
| | - Chao Qin
- Barshop Institute for Longevity and Aging Studies, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229-3900, USA
| | - Gail Celio
- University Imaging Centers, University of Minnesota-Twin Cities, Minneapolis, MN, 55455, USA
| | - Peter Yong
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota-Twin Cities, Minneapolis, MN, 55455, USA
| | - Mark Senders
- University Imaging Centers, University of Minnesota-Twin Cities, Minneapolis, MN, 55455, USA
| | - Xianlin Han
- Barshop Institute for Longevity and Aging Studies, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229-3900, USA
| | - David A Bernlohr
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota-Twin Cities, Minneapolis, MN, 55455, USA
| | - Xiaoli Chen
- Department of Food Science and Nutrition, University of Minnesota-Twin Cities, St. Paul, MN, 55108, USA.
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2
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Pandit S, Goel R, Mishra G. Phosphatidic acid binds to and stimulates the activity of ARGAH2 from Arabidopsis. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 185:344-355. [PMID: 35752016 DOI: 10.1016/j.plaphy.2022.06.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/27/2022] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
Phosphatidic acid (PA) has emerged as an important lipid signal during abiotic and biotic stress conditions such as drought, salinity, freezing, nutrient starvation, wounding and microbial elicitation. PA acts during stress responses primarily via binding and translocating target proteins or through modulating their activity. Owing to the importance of PA during stress signaling and developmental stages, it is imperative to identify PA interacting proteins and decipher their specific roles. In the present study, we have identified PA binding proteins from the leaves of Arabidopsis thaliana. Mass spectroscopy analysis led to the identification of 21 PA binding proteins with known roles in various cellular processes. One of the PA-binding proteins identified during this study, AtARGAH2, was further studied to unravel the role of PA interaction. Recombinant AtARGAH2 binding with immobilized PA on a solid support validated PA-AtARGAH2 binding invitro. PA binding to AtARGAH2 leads to the enhancement of arginase enzymatic activity in a dose dependent manner. Enzyme kinetics of recombinant AtARGAH2 demonstrated a lower Km value in presence of PA, suggesting role of PA in efficient enzyme-substrate binding. This simple approach could systematically be applied to perform an inclusive study on lipid binding proteins to elucidate their role in physiology of plants.
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Affiliation(s)
- Shatakshi Pandit
- Department of Botany, University of Delhi, Delhi, 110007, India.
| | - Renu Goel
- Translational Health Science and Technology Institute, Faridabad, Haryana, 121001, India.
| | - Girish Mishra
- Department of Botany, University of Delhi, Delhi, 110007, India.
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3
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Song M, Meng Q, Jiang X, Liu J, Xiao M, Zhang Z, Wang J, Bai H. Phospholipase D1 promotes cervical cancer progression by activating the RAS pathway. J Cell Mol Med 2022; 26:4244-4253. [PMID: 35775110 PMCID: PMC9344829 DOI: 10.1111/jcmm.17439] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 05/30/2022] [Accepted: 06/01/2022] [Indexed: 12/27/2022] Open
Abstract
This study aimed to further investigate the effect of PLD1 on the biological characteristics of human cervical cancer (CC) cell line, CASKI and the potential related molecular mechanism. CRISPR/Cas9 genome editing technology was used to knock out the PLD1 gene in CASKI cells. Cell function assays were performed to evaluate the effect of PLD1 on the biological function of CASKI cells in vivo and in vitro. A PLD1‐overexpression rescue experiment in these knockout cells was performed to further confirm its function. Two PLD1‐knockout CASKI cell lines (named PC‐11 and PC‐40, which carried the ins1/del4 mutation and del1/del2/ins1 mutation, respectively), were constructed by CRISPR/Cas9. PLD1 was overexpressed in these knockout cells (named PC11‐PLD1 and PC40‐PLD1 cells), which rescued the expression of PLD1 by approximately 71.33% and 74.54%, respectively. In vivo, the cell function assay results revealed that compared with wild‐type (WT)‐CASKI cells, the ability of PC‐11 and PC‐40 cells to proliferate, invade and migrate was significantly inhibited. The expression of H‐Ras and phosphorylation of Erk1/2 (p‐Erk1/2) was decreased in PC‐11 and PC‐40 cells compared with WT‐CASKI cells. PC‐11 and PC‐40 cells could sensitize CASKI cells to cisplatin. More importantly, the proliferation, migration and invasion of PC11‐PLD1 and PC40‐PLD1 cells with PLD1 overexpression were significantly improved compared with those of the two types of PLD1 knockout cells. The sensitivity to cisplatin was decreased in PC11‐PLD1 and PC40‐PLD1 cells compared with PC‐11 and PC‐40 cells. In vivo, in the PC‐11 and PC‐40 tumour groups, tumour growth was significantly inhibited and tumour weight (0.95 ± 0.27 g and 0.66 ± 0.43 g vs. 1.59 ± 0.67 g, p = 0.0313 and 0.0108) and volume (1069.41 ± 393.84 and 1077.72 mm3 ± 815.07 vs. 2142.94 ± 577.37 mm3, p = 0.0153 and 0.0128) were significantly reduced compared to those in the WT‐CASKI group. Tumour differentiation of the PC‐11 and PC40 cells was significantly better than that of the WT‐CASKI cells. The immunohistochemistry results confirmed that the expression of H‐Ras and p‐Erk1/2 was decreased in PC‐11 and PC‐40 tumour tissues compared with WT‐CASKI tumour tissues. PLD1 promotes CC progression by activating the RAS pathway. Inhibition of PLD1 may serve as an attractive therapeutic modality for CC.
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Affiliation(s)
- Meiying Song
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China.,Department of Obstetrics and Gynecology, Fuxing Hospital, Capital Medical University, Beijing, China
| | - Qianlong Meng
- Department of Diagnostics of Clinical Laboratory, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China.,The Clinical Research Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Xuan Jiang
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
| | - Jun Liu
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
| | - Meizhu Xiao
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
| | - Zhenyu Zhang
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
| | - Jing Wang
- Department of Diagnostics of Clinical Laboratory, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China.,The Clinical Research Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Huimin Bai
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
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Polymorphisms in common antihypertensive targets: Pharmacogenomic implications for the treatment of cardiovascular disease. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 94:141-182. [PMID: 35659371 DOI: 10.1016/bs.apha.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The idea of personalized medicine came to fruition with sequencing the human genome; however, aside from a few cases, the genetic revolution has yet to materialize. Cardiovascular diseases are the leading cause of death globally, and hypertension is a common prelude to nearly all cardiovascular diseases. Thus, hypertension is an ideal candidate disease to apply tenants of personalized medicine to lessen cardiovascular disease. Herein is a survey that visually depicts the polymorphisms in the top eight antihypertensive targets. Although there are numerous genome-wide association studies regarding cardiovascular disease, few studies look at the effects of receptor polymorphisms on drug treatment. With 17,000+ polymorphisms in the combined target proteins examined, it is expected that some of the clinical variability in the treatment of hypertension is due to polymorphisms in the drug targets. Recent advances in techniques and technology, such as high throughput examination of single mutations, structure prediction, computational power for modeling, and CRISPR models of point mutations, allow for a relatively rapid and comprehensive examination of the effects of known and future polymorphisms on drug affinity and effects. As hypertension is easy to measure and has a plethora of clinically viable ligands, hypertension makes an excellent disease to study pharmacogenomics in the lab and the clinic. If the promises of personalized medicine are to materialize, a concerted effort to examine the effects polymorphisms have on drugs is required. A clinician with the knowledge of a patient's genotype can then prescribe drugs that are optimal for treating that specific patient.
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Seo J, Yun JE, Kim SJ, Chun YS. Lipid metabolic reprogramming by hypoxia-inducible factor-1 in the hypoxic tumour microenvironment. Pflugers Arch 2022; 474:591-601. [PMID: 35348849 DOI: 10.1007/s00424-022-02683-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/10/2022] [Accepted: 03/12/2022] [Indexed: 10/18/2022]
Abstract
Cancer cells rewire metabolic processes to adapt to the nutrient- and oxygen-deprived tumour microenvironment, thereby promoting their proliferation and metastasis. Previous research has shown that modifying glucose metabolism, the Warburg effect, makes glycolytic cancer cells more invasive and aggressive. Lipid metabolism has also been receiving attention because lipids function as energy sources and signalling molecules. Because obesity is a risk factor for various cancer types, targeting lipid metabolism may be a promising cancer therapy. Here, we review the lipid metabolic reprogramming in cancer cells mediated by hypoxia-inducible factor-1 (HIF-1). HIF-1 is the master transcription factor for tumour growth and metastasis by transactivating genes related to proliferation, survival, angiogenesis, invasion, and metabolism. The glucose metabolic shift (the Warburg effect) is mediated by HIF-1. Recent research on HIF-1-related lipid metabolic reprogramming in cancer has confirmed that HIF-1 also modifies lipid accumulation, β-oxidation, and lipolysis in cancer, triggering its progression. Therefore, targeting lipid metabolic alterations by HIF-1 has therapeutic potential for cancer. We summarize the role of the lipid metabolic shift mediated by HIF-1 in cancer and its putative applications for cancer therapy.
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Affiliation(s)
- Jieun Seo
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, South Korea.,Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, South Korea.,Faculty of Engineering, Yokohama National University, Yokohama, 240-8501, Japan.,Kanagawa Institute of Industrial Science and Technology, Kawasaki, 213-0012, Japan
| | - Jeong-Eun Yun
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, South Korea.,Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, South Korea
| | - Sung Joon Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, South Korea.,Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, South Korea.,Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, 03080, South Korea
| | - Yang-Sook Chun
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, South Korea. .,Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, South Korea. .,Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, 03080, South Korea.
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6
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Implication of Ceramide Kinase/C1P in Cancer Development and Progression. Cancers (Basel) 2022; 14:cancers14010227. [PMID: 35008391 PMCID: PMC8750078 DOI: 10.3390/cancers14010227] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/28/2021] [Accepted: 12/30/2021] [Indexed: 12/28/2022] Open
Abstract
Cancer cells rewire their metabolic programs to favor biological processes that promote cell survival, proliferation, and dissemination. Among this relevant reprogramming, sphingolipid metabolism provides metabolites that can favor or oppose these hallmarks of cancer. The sphingolipid ceramide 1-phosphate (C1P) and the enzyme responsible for its biosynthesis, ceramide kinase (CERK), are well established regulators of cell growth and survival in normal, as well as malignant cells through stress-regulated signaling pathways. This metabolite also promotes cell survival, which has been associated with the feedback regulation of other antitumoral sphingolipids or second messengers. C1P also regulates cancer cell invasion and migration of different types of cancer, including lung, breast, pancreas, prostate, or leukemia cells. More recently, CERK and C1P have been implicated in the control of inflammatory responses. The present review provides an updated view on the important role of CERK/C1P in the regulation of cancer cell growth, survival, and dissemination.
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7
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Metz C, Oyanadel C, Jung J, Retamal C, Cancino J, Barra J, Venegas J, Du G, Soza A, González A. Phosphatidic acid-PKA signaling regulates p38 and ERK1/2 functions in ligand-independent EGFR endocytosis. Traffic 2021; 22:345-361. [PMID: 34431177 DOI: 10.1111/tra.12812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 07/27/2021] [Accepted: 08/16/2021] [Indexed: 12/16/2022]
Abstract
Ligand-independent epidermal growth factor receptor (EGFR) endocytosis is inducible by a variety of stress conditions converging upon p38 kinase. A less known pathway involves phosphatidic acid (PA) signaling toward the activation of type 4 phosphodiesterases (PDE4) that decrease cAMP levels and protein kinase A (PKA) activity. This PA/PDE4/PKA pathway is triggered with propranolol used to inhibit PA hydrolysis and induces clathrin-dependent and clathrin-independent endocytosis, followed by reversible accumulation of EGFR in recycling endosomes. Here we give further evidence of this signaling pathway using biosensors of PA, cAMP, and PKA in live cells and then show that it activates p38 and ERK1/2 downstream the PKA inhibition. Clathrin-silencing and IN/SUR experiments involved the activity of p38 in the clathrin-dependent route, while ERK1/2 mediates clathrin-independent EGFR endocytosis. The PA/PDE4/PKA pathway selectively increases the EGFR endocytic rate without affecting LDLR and TfR constitute endocytosis. This selectiveness is probably because of EGFR phosphorylation, as detected in Th1046/1047 and Ser669 residues. The EGFR accumulates at perinuclear recycling endosomes colocalizing with TfR, fluorescent transferrin, and Rab11, while a small proportion distributes to Alix-endosomes. A non-selective recycling arrest includes LDLR and TfR in a reversible manner. The PA/PDE4/PKA pathway involving both p38 and ERK1/2 expands the possibilities of EGFR transmodulation and interference in cancer.
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Affiliation(s)
- Claudia Metz
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Claudia Oyanadel
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Juan Jung
- Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudio Retamal
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Jorge Cancino
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Jonathan Barra
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Jaime Venegas
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Guangwei Du
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Andrea Soza
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Alfonso González
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile.,Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile.,Fundación Ciencia y Vida, Santiago, Chile
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8
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Yu J, Hu D, Cheng Y, Guo J, Wang Y, Tan Z, Peng J, Zhou H. Lipidomics and transcriptomics analyses of altered lipid species and pathways in oxaliplatin-treated colorectal cancer cells. J Pharm Biomed Anal 2021; 200:114077. [PMID: 33892396 DOI: 10.1016/j.jpba.2021.114077] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 03/13/2021] [Accepted: 04/12/2021] [Indexed: 12/17/2022]
Abstract
Drug resistance and adverse reactions to oxaliplatin remain a considerable issue in clinical practice. Emerging evidence has suggested that alterations in the lipid metabolism during drug therapy affect cancer cells. To gain insight into the important process of lipid metabolism, we investigated the lipid and gene expression profile changes in HT29 cells treated with oxaliplatin. A total of 1403 lipid species from 16 lipid classes were identified by UHPLC-MS. Interestingly, phospholipids, including phosphatidylglycerol (PG), phosphatidic acid (PA), phosphatidylcholine (PC), and most of phosphatidylethanolamine (PE) with polyunsaturated fatty acid (PUFA) chains, were significantly higher due to oxaliplatin treatment, while triacylglycerols (TAGs) with a saturated fatty acid chain or monounsaturated fatty acid were significantly downregulated. Gene Set Enrichment Analysis (GSEA) based on RNA sequencing data suggested that neutral lipid metabolism was enriched in the control group, whereas the phospholipid metabolic process was enriched in the oxaliplatin-treated group. We observed that altered lipid metabolism enzyme genes were involved in the synthesis and lipolysis of TAGs and the Lands cycle pathway based on the network between the core lipid-related gene and lipid species, which was further verified by qRT-PCR. In summary, our findings revealed that oxaliplatin impressed a specific lipid profile signature and lipid transcriptional reprogramming in HT29 cells, which provides new insights into biomarker discovery and pathways for overcoming drug resistance and adverse reactions.
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Affiliation(s)
- Jing Yu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China
| | - Dongli Hu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China
| | - Yu Cheng
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China
| | - Jiwei Guo
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China
| | - Yicheng Wang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China
| | - Zhirong Tan
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China
| | - Jingbo Peng
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China.
| | - Honghao Zhou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, PR China; Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 110 Xiangya Road, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, 110 Xiangya Road, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, 87 Xiangya Road, Changsha 410008, Hunan, PR China.
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9
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Phosphatidic acid-mediated binding and mammalian cell internalization of the Vibrio cholerae cytotoxin MakA. PLoS Pathog 2021; 17:e1009414. [PMID: 33735319 PMCID: PMC8009392 DOI: 10.1371/journal.ppat.1009414] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 03/30/2021] [Accepted: 02/22/2021] [Indexed: 01/08/2023] Open
Abstract
Vibrio cholerae is a noninvasive intestinal pathogen extensively studied as the causative agent of the human disease cholera. Our recent work identified MakA as a potent virulence factor of V. cholerae in both Caenorhabditis elegans and zebrafish, prompting us to investigate the potential contribution of MakA to pathogenesis also in mammalian hosts. In this study, we demonstrate that the MakA protein could induce autophagy and cytotoxicity of target cells. In addition, we observed that phosphatidic acid (PA)-mediated MakA-binding to the host cell plasma membranes promoted macropinocytosis resulting in the formation of an endomembrane-rich aggregate and vacuolation in intoxicated cells that lead to induction of autophagy and dysfunction of intracellular organelles. Moreover, we functionally characterized the molecular basis of the MakA interaction with PA and identified that the N-terminal domain of MakA is required for its binding to PA and thereby for cell toxicity. Furthermore, we observed that the ΔmakA mutant outcompeted the wild-type V. cholerae strain A1552 in the adult mouse infection model. Based on the findings revealing mechanistic insights into the dynamic process of MakA-induced autophagy and cytotoxicity we discuss the potential role played by the MakA protein during late stages of cholera infection as an anti-colonization factor. Vibrio cholerae is the cause of cholera, an infectious disease causing watery diarrhea that can lead to fatal dehydration. The bacteria can readily adapt to different environments, such as from its natural aquatic habitats to the human digestive system. Recently, we reported a novel V. cholerae cytotoxin, MakA that functions as a potent virulence factor in C. elegans and zebrafish. Here we identified phosphatidic acid as a lipid target for MakA interaction with mammalian cells. This interaction promoted macropinocytosis resulting in the formation of an endomembrane-rich aggregate in intoxicated cells that ultimately lead to activation of autophagy. Importantly, data from bacterial colonization in a mouse infection model suggested that MakA might act as an anti-colonization factor of V. cholerae, presumably expressed during later stage(s) of infection. MakA might be explored as a new target for diagnostics and therapeutic developments against V. cholerae infections. Our findings will contribute to further understanding of the virulence, colonization and post-infection spread of V. cholerae.
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10
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Phosphatidic Acid Stimulates Myoblast Proliferation through Interaction with LPA1 and LPA2 Receptors. Int J Mol Sci 2021; 22:ijms22031452. [PMID: 33535610 PMCID: PMC7867176 DOI: 10.3390/ijms22031452] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 01/19/2021] [Indexed: 12/31/2022] Open
Abstract
Phosphatidic acid (PA) is a bioactive phospholipid capable of regulating key biological functions, including neutrophil respiratory burst, chemotaxis, or cell growth and differentiation. However, the mechanisms whereby PA exerts these actions are not completely understood. In this work, we show that PA stimulates myoblast proliferation, as determined by measuring the incorporation of [3H]thymidine into DNA and by staining the cells with crystal violet. PA induced the rapid phosphorylation of Akt and ERK1/2, and pretreatment of the cells with specific small interferin RNA (siRNA) to silence the genes encoding these kinases, or with selective pharmacologic inhibitors, blocked PA-stimulated myoblast proliferation. The mitogenic effects of PA were abolished by the preincubation of the myoblasts with pertussis toxin, a Gi protein inhibitor, suggesting the implication of Gi protein-coupled receptors in this action. Although some of the effects of PA have been associated with its possible conversion to lysoPA (LPA), treatment of the myoblasts with PA for up to 60 min did not produce any significant amount of LPA in these cells. Of interest, pharmacological blockade of the LPA receptors 1 and 2, or specific siRNA to silence the genes encoding these receptors, abolished PA-stimulated myoblast proliferation. Moreover, PA was able to compete with LPA for binding to LPA receptors, suggesting that PA can act as a ligand of LPA receptors. It can be concluded that PA stimulates myoblast proliferation through interaction with LPA1 and LPA2 receptors and the subsequent activation of the PI3K/Akt and MEK/ERK1-2 pathways, independently of LPA formation.
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11
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Tang X, Brindley DN. Lipid Phosphate Phosphatases and Cancer. Biomolecules 2020; 10:biom10091263. [PMID: 32887262 PMCID: PMC7564803 DOI: 10.3390/biom10091263] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 08/28/2020] [Accepted: 08/30/2020] [Indexed: 12/22/2022] Open
Abstract
Lipid phosphate phosphatases (LPPs) are a group of three enzymes (LPP1–3) that belong to a phospholipid phosphatase (PLPP) family. The LPPs dephosphorylate a wide spectrum of bioactive lipid phosphates, among which lysophosphatidate (LPA) and sphingosine 1-phosphate (S1P) are two important extracellular signaling molecules. The LPPs are integral membrane proteins, which are localized on plasma membranes and intracellular membranes, including the endoplasmic reticulum and Golgi network. LPPs regulate signaling transduction in cancer cells and demonstrate different effects in cancer progression through the breakdown of extracellular LPA and S1P and other intracellular substrates. This review is intended to summarize an up-to-date understanding about the functions of LPPs in cancers.
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Affiliation(s)
- Xiaoyun Tang
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2S2, Canada;
- Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - David N. Brindley
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2S2, Canada;
- Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2E1, Canada
- Correspondence:
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12
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Zhao W, Cao L, Ying H, Zhang W, Li D, Zhu X, Xue W, Wu S, Cao M, Fu C, Qi H, Hao Y, Tang YC, Qin J, Zhong TP, Lin X, Yu L, Li X, Li L, Wu D, Pan W. Endothelial CDS2 deficiency causes VEGFA-mediated vascular regression and tumor inhibition. Cell Res 2019; 29:895-910. [PMID: 31501519 PMCID: PMC6889172 DOI: 10.1038/s41422-019-0229-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 08/23/2019] [Indexed: 01/06/2023] Open
Abstract
The response of endothelial cells to signaling stimulation is critical for vascular morphogenesis, homeostasis and function. Vascular endothelial growth factor-a (VEGFA) has been commonly recognized as a pro-angiogenic factor in vertebrate developmental, physiological and pathological conditions for decades. Here we report a novel finding that genetic ablation of CDP-diacylglycerol synthetase-2 (CDS2), a metabolic enzyme that controls phosphoinositide recycling, switches the output of VEGFA signaling from promoting angiogenesis to unexpectedly inducing vessel regression. Live imaging analysis uncovered the presence of reverse migration of the angiogenic endothelium in cds2 mutant zebrafish upon VEGFA stimulation, and endothelium regression also occurred in postnatal retina and implanted tumor models in mice. In tumor models, CDS2 deficiency enhanced the level of tumor-secreted VEGFA, which in-turn trapped tumors into a VEGFA-induced vessel regression situation, leading to suppression of tumor growth. Mechanistically, VEGFA stimulation reduced phosphatidylinositol (4,5)-bisphosphate (PIP2) availability in the absence of CDS2-controlled-phosphoinositide metabolism, subsequently causing phosphatidylinositol (3,4,5)-triphosphate (PIP3) deficiency and FOXO1 activation to trigger regression of CDS2-null endothelium. Thus, our data indicate that the effect of VEGFA on vasculature is context-dependent and can be converted from angiogenesis to vascular regression.
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Affiliation(s)
- Wencao Zhao
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Le Cao
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Hanru Ying
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai, China
| | - Wenjuan Zhang
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Dantong Li
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Xiaolong Zhu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Molecular Medicine, East China Normal University School of Life Sciences, Shanghai, China
| | - Wenzhi Xue
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Shuang Wu
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Mengye Cao
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Cong Fu
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Haonan Qi
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Yimei Hao
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Yun-Chi Tang
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Jun Qin
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Tao P Zhong
- Shanghai Key Laboratory of Regulatory Biology, Institute of Molecular Medicine, East China Normal University School of Life Sciences, Shanghai, China
| | - Xiaoxi Lin
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai, China.,Innovative Research Team of High-level Local University in Shanghai, Shanghai, China
| | - Luyang Yu
- Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Xuri Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lin Li
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, CAS, Shanghai, China
| | - Dianqing Wu
- Department of Pharmacology, Vascular Biology and Therapeutic Program, School of Medicine, Yale University, New Haven, CT, USA
| | - Weijun Pan
- Key Laboratory of Tissue Microenvironment and Tumor, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China. .,Innovative Research Team of High-level Local University in Shanghai, Shanghai, China.
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13
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Abumanhal-Masarweh H, da Silva D, Poley M, Zinger A, Goldman E, Krinsky N, Kleiner R, Shenbach G, Schroeder JE, Shklover J, Shainsky-Roitman J, Schroeder A. Tailoring the lipid composition of nanoparticles modulates their cellular uptake and affects the viability of triple negative breast cancer cells. J Control Release 2019; 307:331-341. [PMID: 31238049 DOI: 10.1016/j.jconrel.2019.06.025] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 06/09/2019] [Accepted: 06/21/2019] [Indexed: 11/16/2022]
Abstract
Lipid nanoparticles are used widely as anticancer drug and gene delivery systems. Internalizing into the target cell is a prerequisite for the proper activity of many nanoparticulate drugs. We show here, that the lipid composition of a nanoparticle affects its ability to internalize into triple-negative breast cancer cells. The lipid headgroup had the greatest effect on enhancing cellular uptake compared to other segments of the molecule. Having a receptor-targeted headgroup induced the greatest increase in cellular uptake, followed by cationic amine headgroups, both being superior to neutral (zwitterion) phosphatidylcholine or to negatively-charged headgroups. The lipid tails also affected the magnitude of cellular uptake. Longer acyl chains facilitated greater liposomal cellular uptake compared to shorter tails, 18:0 > 16:0 > 14:0. When having the same lipid tail length, unsaturated lipids were superior to saturated ones, 18:1 > 18:0. Interestingly, liposomes composed of phospholipids having 14:0 or 12:0-carbon-long-tails, such as DMPC and DLPC, decreased cell viability in a concertation dependent manner, due to a destabilizing effect these lipids had on the cancer cell membrane. Contrarily, liposomes composed of phospholipids having longer carbon tails (16:0 and 18:0), such as DPPC and HSPC, enhanced cancer cell proliferation. This effect is attributed to the integration of the exogenous liposomal lipids into the cancer-cell membrane, supporting the proliferation process. Cholesterol is a common lipid additive in nanoscale formulations, rigidifying the membrane and stabilizing its structure. Liposomes composed of DMPC (14:0) showed increased cellular uptake when enriched with cholesterol, both by endocytosis and by fusion. Contrarily, the effect of cholesterol on HSPC (18:0) liposomal uptake was minimal. Furthermore, the concentration of nanoparticles in solution affected their cellular uptake. The higher the concentration of nanoparticles the greater the absolute number of nanoparticles taken up per cell. However, the efficiency of nanoparticle uptake, i.e. the percent of nanoparticles taken up by cells, decreased as the concentration of nanoparticles increased. This study demonstrates that tuning the lipid composition and concentration of nanoscale drug delivery systems can be leveraged to modulate their cellular uptake.
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Affiliation(s)
- Hanan Abumanhal-Masarweh
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel; Russell Berrie Nanotechnology Institute, The Norman Seiden Multidisciplinary Graduate program, Technion-Israel Institute of Technology, Haifa 3200, Israel
| | - Dana da Silva
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Maria Poley
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Assaf Zinger
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Evgenya Goldman
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Nitzan Krinsky
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Ron Kleiner
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Gal Shenbach
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Josh E Schroeder
- Department of Orthopedic Surgery, Hadassah Medical Center, Jerusalem 91120, Israel
| | - Jeny Shklover
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Janna Shainsky-Roitman
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Avi Schroeder
- Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
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14
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Directly light-regulated binding of RGS-LOV photoreceptors to anionic membrane phospholipids. Proc Natl Acad Sci U S A 2018; 115:E7720-E7727. [PMID: 30065115 PMCID: PMC6099885 DOI: 10.1073/pnas.1802832115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Light–oxygen–voltage (LOV) domain photoreceptors are found ubiquitously in nature and possess highly diverse signaling roles and mechanisms. Here, we show that a class of fungal LOV proteins dynamically associates with anionic plasma membrane phospholipids by a blue light-switched electrostatic interaction. This reversible association is rapidly triggered by blue light and ceases within seconds when illumination ceases. Within the native host, we predict that these proteins regulate G-protein signaling by the controlled recruitment of fused regulator of G-protein signaling (RGS) domains; in applied contexts, we anticipate that engineered chimeric versions of such proteins will be useful for rapid optogenetic membrane localization of fused proteins through direct interaction with the membrane itself, without requiring additional components to direct subcellular localization. We report natural light–oxygen–voltage (LOV) photoreceptors with a blue light-switched, high-affinity (KD ∼ 10−7 M), and direct electrostatic interaction with anionic phospholipids. Membrane localization of one such photoreceptor, BcLOV4 from Botrytis cinerea, is directly coupled to its flavin photocycle, and is mediated by a polybasic amphipathic helix in the linker region between the LOV sensor and its C-terminal domain of unknown function (DUF), as revealed through a combination of bioinformatics, computational protein modeling, structure–function studies, and optogenetic assays in yeast and mammalian cell line expression systems. In model systems, BcLOV4 rapidly translocates from the cytosol to plasma membrane (∼1 second). The reversible electrostatic interaction is nonselective among anionic phospholipids, exhibiting binding strengths dependent on the total anionic content of the membrane without preference for a specific headgroup. The in vitro and cellular responses were also observed with a BcLOV4 homolog and thus are likely to be general across the dikarya LOV class, whose members are associated with regulator of G-protein signaling (RGS) domains. Natural photoreceptors are not previously known to directly associate with membrane phospholipids in a light-dependent manner, and thus this work establishes both a photosensory signal transmission mode and a single-component optogenetic tool with rapid membrane localization kinetics that approaches the diffusion limit.
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15
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Busnelli M, Manzini S, Parolini C, Escalante-Alcalde D, Chiesa G. Lipid phosphate phosphatase 3 in vascular pathophysiology. Atherosclerosis 2018. [DOI: 10.1016/j.atherosclerosis.2018.02.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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16
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Abstract
SIGNIFICANCE Peroxiredoxins (Prxs) are thiol peroxidases with multiple functions in the antioxidant defense and redox signaling network of the cell. Our progressing understanding assigns both local and global significance to plant Prxs, which are grouped in four Prx types. In plants they are localized to the cytosol, mitochondrion, plastid, and nucleus. Antioxidant defense is fundamentally connected to redox signaling, cellular communication, and acclimation. The thiol-disulfide network is central part of the stress sensing and processing response and integrates information input with redox regulation. Recent Advances: Prxs function both as redox sensory system within the network and redox-dependent interactors. The processes directly or indirectly targeted by Prxs include gene expression, post-transcriptional reactions, including translation, post-translational regulation, and switching or tuning of metabolic pathways, and other cell activities. The most advanced knowledge is available for the chloroplast 2-CysPrx wherein recently a solid interactome has been defined. An in silico analysis of protein structure and coexpression reinforces new insights into the 2-CysPrx functionality. CRITICAL ISSUES Up to now, Prxs often have been investigated for local properties of enzyme activity. In vitro and ex vivo work with mutants will reveal the ability of Prxs to interfere with multiple cellular components, including crosstalk with Ca2+-linked signaling pathways, hormone signaling, and protein homeostasis. FUTURE DIRECTIONS Complementation of the Prxs knockout lines with variants that mimic specific states, namely devoid of peroxidase activity, lacking the oligomerization ability, resembling the hyperoxidized decamer, or with truncated C-terminus, should allow dissecting the roles as thiol peroxidase, oxidant, interaction partner, and chaperone. Antioxid. Redox Signal. 28, 609-624.
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Affiliation(s)
- Michael Liebthal
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld , Bielefeld, Germany
| | - Daniel Maynard
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld , Bielefeld, Germany
| | - Karl-Josef Dietz
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld , Bielefeld, Germany
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17
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Zhu M, Foreman DP, O'Brien SA, Jin Y, Zhang W. Phospholipase D in TCR-Mediated Signaling and T Cell Activation. THE JOURNAL OF IMMUNOLOGY 2018; 200:2165-2173. [PMID: 29386256 DOI: 10.4049/jimmunol.1701291] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 01/03/2018] [Indexed: 01/11/2023]
Abstract
Phospholipase D (PLD) is an enzyme that catalyzes the hydrolysis of phosphatidylcholine, the major phospholipid in the plasma membrane, to generate an important signaling lipid, phosphatidic acid. Phosphatidic acid is a second messenger that regulates vesicular trafficking, cytoskeletal reorganization, and cell signaling in immune cells and other cell types. Published studies, using pharmacological inhibitors or protein overexpression, indicate that PLD plays a positive role in TCR-mediated signaling and cell activation. In this study, we used mice deficient in PLD1, PLD2, or both to assess the function of these enzymes in T cells. Our data showed that PLD1 deficiency impaired TCR-mediated signaling, T cell expansion, and effector function during immune responses against Listeria monocytogenes; however, PLD2 deficiency had a minimal impact on T cells. Biochemical analysis indicated that PLD1 deficiency affected Akt and PKCθ activation. In addition, it impaired TCR downregulation and the secondary T cell response. Together, our results suggested that PLD1 plays an important role in T cell activation.
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Affiliation(s)
- Minghua Zhu
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Daniel P Foreman
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Sarah A O'Brien
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Yuefei Jin
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Weiguo Zhang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
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18
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Developmental neurotoxicity of the hippocampus following in utero exposure to methylmercury: impairment in cell signaling. Arch Toxicol 2017; 92:513-527. [PMID: 28821999 DOI: 10.1007/s00204-017-2042-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 08/10/2017] [Indexed: 01/01/2023]
Abstract
In this study, we assessed some hippocampal signaling cascades and behavioral impairments in 30-day-old rat pups prenatally exposed to methylmercury (MeHg). Pregnant rats were exposed to 1.0 or 2.0 mg/kg MeHg by gavage in alternated days from gestational day 5 until parturition. We found increased anxiety-like and decreased exploration behavior evaluated by open field test and deficit of both short- and long-term memories by novel object recognition task, respectively, in MeHg-treated pups. Downregulated PI3K/Akt/mTOR pathway and activated/hypophosphorylated (Ser9) GSK3β in MeHg-treated pups could be upstream of hyperphosphorylated Tau (Ser396) destabilizing microtubules and contributing to neural dysfunction in the hippocampus of these rats. Hyperphosphorylated/activated p38MAPK and downregulated phosphoErk1/2 support a role for mitogen-activated protein kinase (MAPK) cascade on MeHg neurotoxicity. Decreased receptor of advanced glycation end products (RAGE) immunocontent supports the assumption that downregulated RAGE/Erk1/2 pathway could be involved in hypophosphorylated lysine/serine/proline (KSP) repeats on neurofilament subunits and disturbed axonal transport. Downregulated myelin basic protein (MBP), the major myelin protein, is compatible with dysmyelination and neurofilament hypophosphorylation. Increased glial fibrillary acidic protein (GFAP) levels suggest reactive astrocytes, and active apoptotic pathways BAD/BCL-2, BAX/BCL-XL, and caspase 3 suggest cell death. Taken together, our findings get light on important signaling mechanisms that could underlie the behavioral deficits in 30-day-old pups prenatally exposed to MeHg.
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Marchan R, Büttner B, Lambert J, Edlund K, Glaeser I, Blaszkewicz M, Leonhardt G, Marienhoff L, Kaszta D, Anft M, Watzl C, Madjar K, Grinberg M, Rempel E, Hergenröder R, Selinski S, Rahnenführer J, Lesjak MS, Stewart JD, Cadenas C, Hengstler JG. Glycerol-3-phosphate Acyltransferase 1 Promotes Tumor Cell Migration and Poor Survival in Ovarian Carcinoma. Cancer Res 2017; 77:4589-4601. [DOI: 10.1158/0008-5472.can-16-2065] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 04/18/2017] [Accepted: 06/20/2017] [Indexed: 11/16/2022]
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Chen SS, Hu Z, Zhong XP. Diacylglycerol Kinases in T Cell Tolerance and Effector Function. Front Cell Dev Biol 2016; 4:130. [PMID: 27891502 PMCID: PMC5103287 DOI: 10.3389/fcell.2016.00130] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/27/2016] [Indexed: 12/21/2022] Open
Abstract
Diacylglycerol kinases (DGKs) are a family of enzymes that regulate the relative levels of diacylglycerol (DAG) and phosphatidic acid (PA) in cells by phosphorylating DAG to produce PA. Both DAG and PA are important second messengers cascading T cell receptor (TCR) signal by recruiting multiple effector molecules, such as RasGRP1, PKCθ, and mTOR. Studies have revealed important physiological functions of DGKs in the regulation of receptor signaling and the development and activation of immune cells. In this review, we will focus on recent progresses in our understanding of two DGK isoforms, α and ζ, in CD8 T effector and memory cell differentiation, regulatory T cell development and function, and invariant NKT cell development and effector lineage differentiation.
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Affiliation(s)
- Shelley S Chen
- Division of Allergy and Immunology, Department of Pediatrics, Duke University Medical Center Durham, NC, USA
| | - Zhiming Hu
- Division of Allergy and Immunology, Department of Pediatrics, Duke University Medical CenterDurham, NC, USA; Institute of Biotherapy, School of Biotechnology, Southern Medical UniversityGuangzhou, China
| | - Xiao-Ping Zhong
- Division of Allergy and Immunology, Department of Pediatrics, Duke University Medical CenterDurham, NC, USA; Department of Immunology, Duke University Medical CenterDurham, NC, USA; Hematologic Malignancies and Cellular Therapies Program, Duke Cancer Institute, Duke University Medical CenterDurham, NC, USA
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Escalante G, Alencar M, Haddock B, Harvey P. The effects of phosphatidic acid supplementation on strength, body composition, muscular endurance, power, agility, and vertical jump in resistance trained men. J Int Soc Sports Nutr 2016; 13:24. [PMID: 27274715 PMCID: PMC4891923 DOI: 10.1186/s12970-016-0135-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/27/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Phosphatidic acid (PA) is a lipid messenger that has been shown to increase muscle protein synthesis via signaling stimulation of the mammalian target of rapamycin (mTOR). MaxxTOR® (MT) is a supplement that contains PA as the main active ingredient but also contains other synergistic mTOR signaling substances including L-Leucine, Beta-Hydroxy-Beta-Methylbutyrate (HMB), and Vitamin D3. METHODS Eighteen healthy strength-trained males were randomly assigned to a group that either consumed MT (n = 8, 22.0 +/- 2.5 years; 175.8 +/- 11.5 cm; 80.3 +/- 15.1 kg) or a placebo (PLA) (n = 10, 25.6 +/- 4.2 years; 174.8 +/- 9.0 cm; 88.6 +/- 16.6 kg) as part of a double-blind, placebo controlled pre/post experimental design. All participants volunteered to complete the three day per week resistance training protocol for the eight week study duration. To determine the effects of MT, participants were tested on one repetition maximum (1RM) leg press strength (LP), 1RM bench press strength (BP), push-ups to failure (PU), vertical jump (VJ), pro-agility shuttle time (AG), peak power output (P), lean body mass (LBM), fat mass (FM), and thigh muscle mass (TMM). Subjects were placed and monitored on an isocaloric diet consisting of 25 protein, 50 carbohydrates, and 25 % fat by a registered dietitian. Separate two-way mixed factorial repeated measures ANOVA's (time [Pre, Post] x group [MT and PLA] were used to investigate strength, body composition, and other performance changes. Post-hoc tests were applied as appropriate. Analysis were performed via SPSS with significance at (p ≤ 0.05). RESULTS There was a significant main effect (F(1,16) = 33.30, p < 0.001) for LBM where MT significantly increased LBM when compared to the PLA group (p < 0.001). Additionally, there was a significant main effect for LP (F(1,16) = 666.74, p < 0.001) and BP (F(1,16) = 126.36, p < 0.001) where both increased significantly more in MT than PLA group (p < 0.001). No significant differences between MT and PLA were noted for FM, TMM, VJ, AG, P, or PU. CONCLUSION The results of this eight week trial suggest that the addition of MaxxTOR® to a 3-day per week resistance training program can positively impact LBM and strength beyond the results found with exercise alone.
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Affiliation(s)
- Guillermo Escalante
- California State University- San Bernardino, 5500 University Parkway, San Bernardino, CA 92407 USA
| | - Michelle Alencar
- California State University- Long Beach, 1250 Bellflower Boulevard, Long Beach, CA 90840 USA
| | - Bryan Haddock
- California State University- San Bernardino, 5500 University Parkway, San Bernardino, CA 92407 USA
| | - Phillip Harvey
- Max Muscle Sports Nutrition, 210 West Taft Avenue, Orange, CA 92865 USA ; University of Phoenix, San Diego Campus, 9645 Granite Ridge Drive, San Diego, CA 92123 USA
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22
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Friday SC, Fox DA. Phospholipase D enzymes facilitate IL-17- and TNFα-induced expression of proinflammatory genes in rheumatoid arthritis synovial fibroblasts (RASF). Immunol Lett 2016; 174:9-18. [DOI: 10.1016/j.imlet.2016.04.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/01/2016] [Accepted: 04/01/2016] [Indexed: 11/30/2022]
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23
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PLD1 participates in BDNF-induced signalling in cortical neurons. Sci Rep 2015; 5:14778. [PMID: 26437780 PMCID: PMC4594037 DOI: 10.1038/srep14778] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 09/09/2015] [Indexed: 01/07/2023] Open
Abstract
The brain-derived neurotrophic factor BDNF plays a critical role in neuronal development and the induction of L-LTP at glutamatergic synapses in several brain regions. However, the cellular and molecular mechanisms underlying these BDNF effects have not been firmly established. Using in vitro cultures of cortical neurons from knockout mice for Pld1 and Rsk2, BDNF was observed to induce a rapid RSK2-dependent activation of PLD and to stimulate BDNF ERK1/2-CREB and mTor-S6K signalling pathways, but these effects were greatly reduced in Pld1(-/-) neurons. Furthermore, phospho-CREB did not accumulate in the nucleus, whereas overexpression of PLD1 amplified the BDNF-dependent nuclear recruitment of phospho-ERK1/2 and phospho-CREB. This BDNF retrograde signalling was prevented in cells silenced for the scaffolding protein PEA15, a protein which complexes with PLD1, ERK1/2, and RSK2 after BDNF treatment. Finally PLD1, ERK1/2, and RSK2 partially colocalized on endosomal structures, suggesting that these proteins are part of the molecular module responsible for BDNF signalling in cortical neurons.
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Rogasevskaia TP, Coorssen JR. The Role of Phospholipase D in Regulated Exocytosis. J Biol Chem 2015; 290:28683-96. [PMID: 26433011 DOI: 10.1074/jbc.m115.681429] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Indexed: 11/06/2022] Open
Abstract
There are a diversity of interpretations concerning the possible roles of phospholipase D and its biologically active product phosphatidic acid in the late, Ca(2+)-triggered steps of regulated exocytosis. To quantitatively address functional and molecular aspects of the involvement of phospholipase D-derived phosphatidic acid in regulated exocytosis, we used an array of phospholipase D inhibitors for ex vivo and in vitro treatments of sea urchin eggs and isolated cortices and cortical vesicles, respectively, to study late steps of exocytosis, including docking/priming and fusion. The experiments with fluorescent phosphatidylcholine reveal a low level of phospholipase D activity associated with cortical vesicles but a significantly higher activity on the plasma membrane. The effects of phospholipase D activity and its product phosphatidic acid on the Ca(2+) sensitivity and rate of fusion correlate with modulatory upstream roles in docking and priming rather than to direct effects on fusion per se.
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Affiliation(s)
| | - Jens R Coorssen
- Department of Molecular Physiology, School of Medicine and the Molecular Medicine Research Group, Western Sydney University, Penrith NSW 2751, Australia
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Zhu M, Zou J, Li T, O'Brien SA, Zhang Y, Ogden S, Zhang W. Differential Roles of Phospholipase D Proteins in FcεRI-Mediated Signaling and Mast Cell Function. THE JOURNAL OF IMMUNOLOGY 2015; 195:4492-502. [PMID: 26392467 DOI: 10.4049/jimmunol.1500665] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 08/20/2015] [Indexed: 12/30/2022]
Abstract
Phospholipase D (PLD) proteins are enzymes that catalyze the hydrolysis of phosphatidylcholine to generate an important signaling lipid, phosphatidic acid. Phosphatidic acid is a putative second messenger implicated in the regulation of vesicular trafficking and cytoskeletal reorganization. Previous studies using inhibitors and overexpression of PLD proteins indicate that PLD1 and PLD2 play positive roles in FcεRI-mediated signaling and mast cell function. We used mice deficient in PLD1, PLD2, or both to study the function of these enzymes in mast cells. In contrast to published studies, we found that PLD1 deficiency impaired FcεRI-mediated mast cell degranulation; however, PLD2 deficiency enhanced it. Biochemical analysis showed that PLD deficiency affected activation of the PI3K pathway and RhoA. Furthermore, our data indicated that, although PLD1 deficiency impaired F-actin disassembly, PLD2 deficiency enhanced microtubule formation. Together, our results suggested that PLD1 and PLD2, two proteins that catalyze the same enzymatic reaction, regulate different steps in mast cell degranulation.
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Affiliation(s)
- Minghua Zhu
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Jianwei Zou
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Tieshi Li
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Sarah A O'Brien
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Yao Zhang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Sarah Ogden
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Weiguo Zhang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
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Haigh CL, Tumpach C, Drew SC, Collins SJ. The Prion Protein N1 and N2 Cleavage Fragments Bind to Phosphatidylserine and Phosphatidic Acid; Relevance to Stress-Protection Responses. PLoS One 2015; 10:e0134680. [PMID: 26252007 PMCID: PMC4529310 DOI: 10.1371/journal.pone.0134680] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/13/2015] [Indexed: 11/18/2022] Open
Abstract
Internal cleavage of the cellular prion protein generates two well characterised N-terminal fragments, N1 and N2. These fragments have been shown to bind to anionic phospholipids at low pH. We sought to investigate binding with other lipid moieties and queried how such interactions could be relevant to the cellular functions of these fragments. Both N1 and N2 bound phosphatidylserine (PS), as previously reported, and a further interaction with phosphatidic acid (PA) was also identified. The specificity of this interaction required the N-terminus, especially the proline motif within the basic amino acids at the N-terminus, together with the copper-binding region (unrelated to copper saturation). Previously, the fragments have been shown to be protective against cellular stresses. In the current study, serum deprivation was used to induce changes in the cellular lipid environment, including externalisation of plasma membrane PS and increased cellular levels of PA. When copper-saturated, N2 could reverse these changes, but N1 could not, suggesting that direct binding of N2 to cellular lipids may be part of the mechanism by which this peptide signals its protective response.
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Affiliation(s)
- Cathryn L. Haigh
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
- * E-mail: (CLH); (SJC)
| | - Carolin Tumpach
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
| | - Simon C. Drew
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
| | - Steven J. Collins
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne Brain Centre, Melbourne, VIC, AUS, 3010
- * E-mail: (CLH); (SJC)
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Kwolek U, Kulig W, Wydro P, Nowakowska M, Róg T, Kepczynski M. Effect of Phosphatidic Acid on Biomembrane: Experimental and Molecular Dynamics Simulations Study. J Phys Chem B 2015; 119:10042-51. [DOI: 10.1021/acs.jpcb.5b03604] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Urszula Kwolek
- Faculty
of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Waldemar Kulig
- Department
of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Paweł Wydro
- Faculty
of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Maria Nowakowska
- Faculty
of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Tomasz Róg
- Department
of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Mariusz Kepczynski
- Faculty
of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
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Affiliation(s)
- Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, University of Miami, Miami, Florida 33136-6129;
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Tang X, Benesch MGK, Brindley DN. Lipid phosphate phosphatases and their roles in mammalian physiology and pathology. J Lipid Res 2015; 56:2048-60. [PMID: 25814022 DOI: 10.1194/jlr.r058362] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Indexed: 12/20/2022] Open
Abstract
Lipid phosphate phosphatases (LPPs) are a group of enzymes that belong to a phosphatase/phosphotransferase family. Mammalian LPPs consist of three isoforms: LPP1, LPP2, and LPP3. They share highly conserved catalytic domains and catalyze the dephosphorylation of a variety of lipid phosphates, including phosphatidate, lysophosphatidate (LPA), sphingosine 1-phosphate (S1P), ceramide 1-phosphate, and diacylglycerol pyrophosphate. LPPs are integral membrane proteins, which are localized on plasma membranes with the active site on the outer leaflet. This enables the LPPs to degrade extracellular LPA and S1P, thereby attenuating their effects on the activation of surface receptors. LPP3 also exhibits noncatalytic effects at the cell surface. LPP expression on internal membranes, such as endoplasmic reticulum and Golgi, facilitates the metabolism of internal lipid phosphates, presumably on the luminal surface of these organelles. This action probably explains the signaling effects of the LPPs, which occur downstream of receptor activation. The three isoforms of LPPs show distinct and nonredundant effects in several physiological and pathological processes including embryo development, vascular function, and tumor progression. This review is intended to present an up-to-date understanding of the physiological and pathological consequences of changing the activities of the different LPPs, especially in relation to cell signaling by LPA and S1P.
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Affiliation(s)
- Xiaoyun Tang
- Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada
| | - Matthew G K Benesch
- Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada
| | - David N Brindley
- Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada
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Fatal attraction: how bacterial adhesins affect host signaling and what we can learn from them. Int J Mol Sci 2015; 16:2626-40. [PMID: 25625516 PMCID: PMC4346855 DOI: 10.3390/ijms16022626] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 12/25/2014] [Accepted: 01/19/2015] [Indexed: 12/20/2022] Open
Abstract
The ability of bacterial species to colonize and infect host organisms is critically dependent upon their capacity to adhere to cellular surfaces of the host. Adherence to cell surfaces is known to be essential for the activation and delivery of certain virulence factors, but can also directly affect host cell signaling to aid bacterial spread and survival. In this review we will discuss the recent advances in the field of bacterial adhesion, how we are beginning to unravel the effects adhesins have on host cell signaling, and how these changes aid the bacteria in terms of their survival and evasion of immune responses. Finally, we will highlight how the exploitation of bacterial adhesins may provide new therapeutic avenues for the treatment of a wide range of bacterial infections.
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Babenko NA, Kharchenko VS. Modulation of Insulin Sensitivity of Hepatocytes by the Pharmacological Downregulation of Phospholipase D. Int J Endocrinol 2015; 2015:794838. [PMID: 26089893 PMCID: PMC4458285 DOI: 10.1155/2015/794838] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 04/30/2015] [Accepted: 05/11/2015] [Indexed: 12/13/2022] Open
Abstract
Background. The role of phospholipase D (PLD) as a positive modulator of glucose uptake activation by insulin in muscle and adipose cells has been demonstrated. The role of PLD in the regulation of glucose metabolism by insulin in the primary hepatocytes has been determined in this study. Methods. For this purpose, we studied effects of inhibitors of PLD on glucose uptake and glycogen synthesis stimulation by insulin. To determine the PLD activity, the method based on determination of products of transphosphatidylation reaction, phosphatidylethanol or phosphatidylbutanol, was used. Results. Inhibition of PLD by a general antagonist (1-butanol) or specific inhibitor, halopemide, or N-hexanoylsphingosine, or by cellular ceramides accumulated in doxorubicin-treated hepatocytes decreased insulin-stimulated glucose metabolism. Doxorubicin-induced hepatocytes resistance to insulin action could be abolished by inhibition of ceramide production. Halopemide could nullify this effect. Addition of propranolol, as well as inhibitors of phosphatidylinositol 3-kinase (PI3-kinase) (wortmannin, LY294002) or suppressors of Akt phosphorylation/activity, luteolin-7-O-glucoside or apigenin-7-O-glucoside, to the culture media could block cell response to insulin action. Conclusion. PLD plays an important role in the insulin signaling in the hepatocytes. PLD is activated downstream of PI3-kinase and Akt and is highly sensitive to ceramide content in the liver cells.
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Affiliation(s)
- Nataliya A. Babenko
- Department of Physiology of Ontogenesis, Biology Research Institute, Karazin Kharkov National University, Svobody Square 4, Kharkov 61022, Ukraine
- *Nataliya A. Babenko:
| | - Vitalina S. Kharchenko
- Department of Physiology of Ontogenesis, Biology Research Institute, Karazin Kharkov National University, Svobody Square 4, Kharkov 61022, Ukraine
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Phosphatidic acid inhibits ceramide 1-phosphate-stimulated macrophage migration. Biochem Pharmacol 2014; 92:642-50. [DOI: 10.1016/j.bcp.2014.10.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/03/2014] [Accepted: 10/06/2014] [Indexed: 02/06/2023]
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Lim J, Stones DH, Hawley CA, Watson CA, Krachler AM. Multivalent adhesion molecule 7 clusters act as signaling platform for host cellular GTPase activation and facilitate epithelial barrier dysfunction. PLoS Pathog 2014; 10:e1004421. [PMID: 25255250 PMCID: PMC4177989 DOI: 10.1371/journal.ppat.1004421] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 08/25/2014] [Indexed: 01/24/2023] Open
Abstract
Vibrio parahaemolyticus is an emerging bacterial pathogen which colonizes the gastrointestinal tract and can cause severe enteritis and bacteraemia. During infection, V. parahaemolyticus primarily attaches to the small intestine, where it causes extensive tissue damage and compromises epithelial barrier integrity. We have previously described that Multivalent Adhesion Molecule (MAM) 7 contributes to initial attachment of V. parahaemolyticus to epithelial cells. Here we show that the bacterial adhesin, through multivalent interactions between surface-induced adhesin clusters and phosphatidic acid lipids in the host cell membrane, induces activation of the small GTPase RhoA and actin rearrangements in host cells. In infection studies with V. parahaemolyticus we further demonstrate that adhesin-triggered activation of the ROCK/LIMK signaling axis is sufficient to redistribute tight junction proteins, leading to a loss of epithelial barrier function. Taken together, these findings show an unprecedented mechanism by which an adhesin acts as assembly platform for a host cellular signaling pathway, which ultimately facilitates breaching of the epithelial barrier by a bacterial pathogen. Vibrio parahaemolyticus is a bacterial pathogen which occurs in marine and estuarine environments. It is a main cause of gastrointestinal illness following the consumption of raw or undercooked seafood. In immunocompromised people, the bacteria can sometimes enter the bloodstream and cause septicemia, a serious and often fatal condition. V. parahaemolyticus attaches to host tissues using adhesive proteins. Multivalent Adhesion Molecule (MAM) 7 is an adhesin which helps the bacteria to hold onto the host cells early on during infection. It does so by binding two different molecules on the host, a protein (fibronectin) and phospholipids called phosphatidic acids. We show that MAM7 does not only play a role in sticking to host cells. By forming adhesin clusters on the host surface and binding to host lipids, it triggers signaling processes in the host. These include activation of RhoA, an important mediator of cytoskeletal dynamics. By doing so, MAM7 perturbs proteins at cellular junctions, which normally maintain the cells in the gut as a tightly sealed layer protective of environmental influences. When bacteria use MAM7 to attach to the intestine, the seals between cells break, permitting bacteria to cross the barrier and cause infection of underlying tissues.
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Affiliation(s)
- Jenson Lim
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Daniel H. Stones
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Catherine Alice Hawley
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Charlie Anne Watson
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Anne Marie Krachler
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail:
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Shaughnessy R, Retamal C, Oyanadel C, Norambuena A, López A, Bravo-Zehnder M, Montecino FJ, Metz C, Soza A, González A. Epidermal growth factor receptor endocytic traffic perturbation by phosphatidate phosphohydrolase inhibition: new strategy against cancer. FEBS J 2014; 281:2172-89. [PMID: 24597955 DOI: 10.1111/febs.12770] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 02/02/2014] [Accepted: 02/26/2014] [Indexed: 01/11/2023]
Abstract
Epidermal growth factor receptor (EGFR) exaggerated (oncogenic) function is currently targeted in cancer treatment with drugs that block receptor ligand binding or tyrosine kinase activity. Because endocytic trafficking is a crucial regulator of EGFR function, its pharmacological perturbation might provide a new anti-tumoral strategy. Inhibition of phosphatidic acid (PA) phosphohydrolase (PAP) activity has been shown to trigger PA signaling towards type 4 phosphodiesterase (PDE4) activation and protein kinase A inhibition, leading to internalization of empty/inactive EGFR. Here, we used propranolol, its l- and d- isomers and desipramine as PAP inhibitors to further explore the effects of PAP inhibition on EGFR endocytic trafficking and its consequences on EGFR-dependent cancer cell line models. PAP inhibition not only made EGFR inaccessible to stimuli but also prolonged the signaling lifetime of ligand-activated EGFR in recycling endosomes. Strikingly, such endocytic perturbations applied in acute/intermittent PAP inhibitor treatments selectively impaired cell proliferation/viability sustained by an exaggerated EGFR function. Phospholipase D inhibition with FIPI (5-fluoro-2-indolyl des-chlorohalopemide) and PDE4 inhibition with rolipram abrogated both the anti-tumoral and endocytic effects of PAP inhibition. Prolonged treatments with a low concentration of PAP inhibitors, although without detectable endocytic effects, still counteracted cell proliferation, induced apoptosis and decreased anchorage-independent growth of cells bearing EGFR oncogenic influences. Overall, our results show that PAP inhibitors can counteract EGFR oncogenic traits, including receptor overexpression or activating mutations resistant to current tyrosine kinase inhibitors, perturbing EGFR endocytic trafficking and perhaps other as yet unknown processes, depending on treatment conditions. This puts PAP activity forward as a new suitable target against EGFR-driven malignancy.
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Affiliation(s)
- Ronan Shaughnessy
- Departamento de Inmunología Clínica y Reumatología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Centro de Envejecimiento y Regeneración, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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Signal integration by lipid-mediated spatial cross talk between Ras nanoclusters. Mol Cell Biol 2013; 34:862-76. [PMID: 24366544 DOI: 10.1128/mcb.01227-13] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipid-anchored Ras GTPases form transient, spatially segregated nanoclusters on the plasma membrane that are essential for high-fidelity signal transmission. The lipid composition of Ras nanoclusters, however, has not previously been investigated. High-resolution spatial mapping shows that different Ras nanoclusters have distinct lipid compositions, indicating that Ras proteins engage in isoform-selective lipid sorting and accounting for different signal outputs from different Ras isoforms. Phosphatidylserine is a common constituent of all Ras nanoclusters but is only an obligate structural component of K-Ras nanoclusters. Segregation of K-Ras and H-Ras into spatially and compositionally distinct lipid assemblies is exquisitely sensitive to plasma membrane phosphatidylserine levels. Phosphatidylserine spatial organization is also modified by Ras nanocluster formation. In consequence, Ras nanoclusters engage in remote lipid-mediated communication, whereby activated H-Ras disrupts the assembly and operation of spatially segregated K-Ras nanoclusters. Computational modeling and experimentation reveal that complex effects of caveolin and cortical actin on Ras nanoclustering are similarly mediated through regulation of phosphatidylserine spatiotemporal dynamics. We conclude that phosphatidylserine maintains the lateral segregation of diverse lipid-based assemblies on the plasma membrane and that lateral connectivity between spatially remote lipid assemblies offers important previously unexplored opportunities for signal integration and signal processing.
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A local, periactive zone endocytic machinery at photoreceptor synapses in close vicinity to synaptic ribbons. J Neurosci 2013; 33:10278-300. [PMID: 23785143 DOI: 10.1523/jneurosci.5048-12.2013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Photoreceptor ribbon synapses are continuously active synapses with large active zones that contain synaptic ribbons. Synaptic ribbons are anchored to the active zones and are associated with large numbers of synaptic vesicles. The base of the ribbon that is located close to L-type voltage-gated Ca(2+) channels is a hotspot of exocytosis. The continuous exocytosis at the ribbon synapse needs to be balanced by compensatory endocytosis. Recent analyses indicated that vesicle recycling at the synaptic ribbon is also an important determinant of synaptic signaling at the photoreceptor synapse. To get insights into mechanisms of vesicle recycling at the photoreceptor ribbon synapse, we performed super-resolution structured illumination microscopy and immunogold electron microscopy to localize major components of the endocytotic membrane retrieval machinery in the photoreceptor synapse of the mouse retina. We found dynamin, syndapin, amphiphysin, and calcineurin, a regulator of activity-dependent endocytosis, to be highly enriched around the active zone and the synaptic ribbon. We present evidence for two clathrin heavy chain variants in the photoreceptor terminal; one is enriched around the synaptic ribbon, whereas the other is localized in the entry region of the terminal. The focal enrichment of endocytic proteins around the synaptic ribbon is consistent with a focal uptake of endocytic markers at that site. This endocytic activity functionally depends on dynamin. These data propose that the presynaptic periactive zone surrounding the synaptic ribbon complex is a hotspot of endocytosis in photoreceptor ribbon synapses.
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Krishna S, Zhong XP. Regulation of Lipid Signaling by Diacylglycerol Kinases during T Cell Development and Function. Front Immunol 2013; 4:178. [PMID: 23847619 PMCID: PMC3701226 DOI: 10.3389/fimmu.2013.00178] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 06/19/2013] [Indexed: 01/14/2023] Open
Abstract
Diacylglycerol (DAG) and phosphatidic acid (PA) are bioactive lipids synthesized when the T cell receptor binds to a cognate peptide-MHC complex. DAG triggers signaling by recruiting Ras guanyl-releasing protein 1, PKCθ, and other effectors, whereas PA binds to effector molecules that include mechanistic target of rapamycin, Src homology region 2 domain-containing phosphatase 1, and Raf1. While DAG-mediated pathways have been shown to play vital roles in T cell development and function, the importance of PA-mediated signals remains less clear. The diacylglycerol kinase (DGK) family of enzymes phosphorylates DAG to produce PA, serving as a molecular switch that regulates the relative levels of these critical second messengers. Two DGK isoforms, α and ζ, are predominantly expressed in T lineage cells and play an important role in conventional αβ T cell development. In mature T cells, the activity of these DGK isoforms aids in the maintenance of self-tolerance by preventing T cell hyper-activation and promoting T cell anergy. In this review, we discuss the roles of DAG-mediated pathways, PA-effectors, and DGKs in T cell development and function. We also highlight recent work that has uncovered previously unappreciated roles for DGK activity, for instance in invariant NKT cell development, anti-tumor and anti-viral CD8 responses, and the directional secretion of soluble effectors.
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Affiliation(s)
- Sruti Krishna
- Department of Pediatrics, Division of Allergy and Immunology, Duke University Medical Center , Durham, NC , USA ; Department of Immunology, Duke University Medical Center , Durham, NC , USA
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Tang SQ, Jiang QY, Yang CF, Zou XT, Dong XY. [Research and development of Lipin family.]. YI CHUAN = HEREDITAS 2012; 32:981-93. [PMID: 20943485 DOI: 10.3724/sp.j.1005.2010.00981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Lipin family including at least three members Lipin 1, Lipin 2, and Lipin 3 is a critical regulatory enzyme identified recently, which plays dual roles in lipid metabolisms. Lipin family has physiological effects not only on regulating lipid metabolism, but also on maintaining normal peripheral nervous functions, liver lipoprotein secretion, cell morphous, reproductive functions, and energy homeostasis. Since mutations in Lipin gene express may be associated with AIDS, insulin resistance, obesity, diabetes mellitus, and the other diseases of metabolic syndrome, Lipin may be a new useful target in treatment of above-mentioned clinical-related diseases. In this article, we focused on discovery, construction features, expression, regulatory mechanism, and biological functions of Lipin, as well as its correlation research with clinical-related diseases.
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Hoffman JR, Stout JR, Williams DR, Wells AJ, Fragala MS, Mangine GT, Gonzalez AM, Emerson NS, McCormack WP, Scanlon TC, Purpura M, Jäger R. Efficacy of phosphatidic acid ingestion on lean body mass, muscle thickness and strength gains in resistance-trained men. J Int Soc Sports Nutr 2012; 9:47. [PMID: 23035701 PMCID: PMC3506449 DOI: 10.1186/1550-2783-9-47] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 09/26/2012] [Indexed: 01/02/2023] Open
Abstract
UNLABELLED BACKGROUND Phosphatidic acid (PA) has been reported to activate the mammalian target of rapamycin (mTOR) signaling pathway and is thought to enhance the anabolic effects of resistance training. The purpose of this pilot study was to examine if oral phosphatidic acid administration can enhance strength, muscle thickness and lean tissue accruement during an 8-week resistance training program. METHODS Sixteen resistance-trained men were randomly assigned to a group that either consumed 750 mg of PA (n = 7, 23.1 ± 4.4 y; 176.7 ± 6.7 cm; 86.5 ± 21.2 kg) or a placebo (PL, n = 9, 22.5 ± 2.0 y; 179.8 ± 5.4 cm; 89.4 ± 13.6 kg) group. During each testing session subjects were assessed for strength (one repetition maximum [1-RM] bench press and squat) and body composition. Muscle thickness and pennation angle were also measured in the vastus lateralis of the subject's dominant leg. RESULTS Subjects ingesting PA demonstrated a 12.7% increase in squat strength and a 2.6% increase in LBM, while subjects consuming PL showed a 9.3% improvement in squat strength and a 0.1% change in LBM. Although parametric analysis was unable to demonstrate significant differences, magnitude based inferences indicated that the Δ change in 1-RM squat showed a likely benefit from PA on increasing lower body strength and a very likely benefit for increasing lean body mass (LBM). CONCLUSIONS Results of this study suggest that a combination of a daily 750 mg PA ingestion, combined with a 4-day per week resistance training program for 8-weeks appears to have a likely benefit on strength improvement, and a very likely benefit on lean tissue accruement in young, resistance trained individuals.
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Affiliation(s)
- Jay R Hoffman
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Jeffrey R Stout
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - David R Williams
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Adam J Wells
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Maren S Fragala
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Gerald T Mangine
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Adam M Gonzalez
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Nadia S Emerson
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - William P McCormack
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Tyler C Scanlon
- Human Performance Laboratory, University of Central Florida, Orlando, 32186, FL, USA
| | - Martin Purpura
- Increnovo LLC, 2138 E. Lafayette Pl, Milwaukee, 53202, WI, USA
| | - Ralf Jäger
- Increnovo LLC, 2138 E. Lafayette Pl, Milwaukee, 53202, WI, USA
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Cell autonomous lipin 1 function is essential for development and maintenance of white and brown adipose tissue. Mol Cell Biol 2012; 32:4794-810. [PMID: 23028044 DOI: 10.1128/mcb.00512-12] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Through analysis of mice with spatially and temporally restricted inactivation of Lpin1, we characterized its cell autonomous function in both white (WAT) and brown (BAT) adipocyte development and maintenance. We observed that the lipin 1 inactivation in adipocytes of aP2(Cre/+)/Lp(fEx2)(-)(3/fEx2)(-)(3) mice resulted in lipodystrophy and the presence of adipocytes with multilocular lipid droplets. We further showed that time-specific loss of lipin 1 in mature adipocytes in aP2(Cre-ERT2/+)/Lp(fEx2)(-)(3/fEx2)(-)(3) mice led to their replacement by newly formed Lpin1-positive adipocytes, thus establishing a role for lipin 1 in mature adipocyte maintenance. Importantly, we observed that the presence of newly formed Lpin1-positive adipocytes in aP2(Cre-ERT2/+)/Lp(fEx2)(-)(3/fEx2)(-)(3) mice protected these animals against WAT inflammation and hepatic steatosis induced by a high-fat diet. Loss of lipin 1 also affected BAT development and function, as revealed by histological changes, defects in the expression of peroxisome proliferator-activated receptor alpha (PPARα), PGC-1α, and UCP1, and functionally by altered cold sensitivity. Finally, our data indicate that phosphatidic acid, which accumulates in WAT of animals lacking lipin 1 function, specifically inhibits differentiation of preadipocytes. Together, these observations firmly demonstrate a cell autonomous role of lipin 1 in WAT and BAT biology and indicate its potential as a therapeutical target for the treatment of obesity.
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Violet PC, Billon-Denis E, Robin P. Inhibition of lipid phosphate phosphatase activity by VPC32183 suppresses the ability of diacylglycerol pyrophosphate to activate ERK(1/2) MAP kinases. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1394-405. [PMID: 22820196 DOI: 10.1016/j.bbalip.2012.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 06/26/2012] [Accepted: 07/11/2012] [Indexed: 11/17/2022]
Abstract
The lipidic metabolite, diacylglycerol pyrophosphate (DGPP), in its dioctanoyl form (DGPP 8:0), has been described as an antagonist for mammalian lysophosphatidic acid (LPA) receptors LPA1 and LPA3. In this study we show that DGPP 8:0 does not antagonize LPA dependent activation of ERK(1/2) MAP kinases but strongly stimulated them in various mammalian cell lines. LPA and DGPP 8:0 stimulation of ERK(1/2) occurred through different pathways. The DGPP 8:0 effect appeared to be dependent on PKC, Raf and MEK but was insensitive to pertussis toxin and did not involve G protein activation. Finally we showed that DGPP 8:0 effect on ERK(1/2) was dependent on its dephosphorylation by a phosphatase activity sharing lipid phosphate phosphatase properties. The inhibition of this phosphatase activity by VPC32183, a previously characterized LPA receptor antagonist, blocked the DGPP 8:0 effect on ERK(1/2) activation. Moreover, down-regulation of lipid phosphate phosphatase 1 (LPP1) expression by RNA interference technique also reduced DGPP 8:0-induced ERK(1/2) activation. Consistently, over expression of LPP1 in HEK293 cells increases DGPP 8:0 hydrolysis and this increased activity was inhibited by VPC32183. In conclusion, DGPP 8:0 does not exert its effect by acting on a G protein coupled receptor, but through its dephosphorylation by LPP1, generating dioctanoyl phosphatidic acid which in turn activates PKC. These results suggest that LPP1 could have a positive regulatory function on cellular signaling processes such as ERK(1/2) activation.
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Affiliation(s)
- Pierre-Christian Violet
- Université Paris-Sud 11, Institut de Biochimie et de Biophysique Moléculaire et Cellulaire, CNRS UMR 8619, 91405 Orsay CEDEX, France
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Wallert M, McCoy A, Voog J, Rastedt D, Taves-Patterson J, Korpi-Steiner N, Canine J, Ngyuen T, Nguyen C, Provost J. α1 -Adrenergic receptor-induced cytoskeletal organization and cell motility in CCL39 fibroblasts requires phospholipase D1. J Cell Biochem 2012; 112:3025-34. [PMID: 21678474 DOI: 10.1002/jcb.23227] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The role of phospholipase D (PLD) in cytoskeletal reorganization, ERK activation, and migration is well established. Both isoforms of PLD (PLD1 and PLD2) can independently activate stress fiber formation and increase ERK phosphorylation. However, the isoform's specificity, upstream activators, and downstream targets of PLD that coordinate this process are less well understood. This study explores the role of α(1) -adrenergic receptor stimulation and its effect on PLD activity. We demonstrate that PLD1 activators, RhoA, and PKCα are critical for stress fiber formation and ERK activation, and enhance the production of phosphatidic acid (PA) upon phenylephrine addition. Ectopic expression of dominant negative PLD1 and not PLD2 blocks ERK activation, inhibits stress fiber formation, and reduces cell motility in CCL39 fibroblasts. Furthermore, we demonstrate the mechanism for PLD1 activation of ERK involves Ras. This work indicates that PLD1 plays a novel role mediating growth factor and cell motility events in α(1) -adrenergic receptor-activated cells.
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Affiliation(s)
- M Wallert
- Departments of Biosciences and Chemistry, Minnesota State University Moorhead, Moorhead, Minnesota 56563, USA
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Lord CC, Betters JL, Ivanova PT, Milne SB, Myers DS, Madenspacher J, Thomas G, Chung S, Liu M, Davis MA, Lee RG, Crooke RM, Graham MJ, Parks JS, Brasaemle DL, Fessler MB, Brown HA, Brown JM. CGI-58/ABHD5-derived signaling lipids regulate systemic inflammation and insulin action. Diabetes 2012; 61:355-63. [PMID: 22228714 PMCID: PMC3266405 DOI: 10.2337/db11-0994] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mutations of comparative gene identification 58 (CGI-58) in humans cause Chanarin-Dorfman syndrome, a rare autosomal recessive disease in which excess triacylglycerol (TAG) accumulates in multiple tissues. CGI-58 recently has been ascribed two distinct biochemical activities, including coactivation of adipose triglyceride lipase and acylation of lysophosphatidic acid (LPA). It is noteworthy that both the substrate (LPA) and the product (phosphatidic acid) of the LPA acyltransferase reaction are well-known signaling lipids. Therefore, we hypothesized that CGI-58 is involved in generating lipid mediators that regulate TAG metabolism and insulin sensitivity. Here, we show that CGI-58 is required for the generation of signaling lipids in response to inflammatory stimuli and that lipid second messengers generated by CGI-58 play a critical role in maintaining the balance between inflammation and insulin action. Furthermore, we show that CGI-58 is necessary for maximal TH1 cytokine signaling in the liver. This novel role for CGI-58 in cytokine signaling may explain why diminished CGI-58 expression causes severe hepatic lipid accumulation yet paradoxically improves hepatic insulin action. Collectively, these findings establish that CGI-58 provides a novel source of signaling lipids. These findings contribute insight into the basic mechanisms linking TH1 cytokine signaling to nutrient metabolism.
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Affiliation(s)
- Caleb C. Lord
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Jenna L. Betters
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Pavlina T. Ivanova
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Stephen B. Milne
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - David S. Myers
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Jennifer Madenspacher
- Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina
| | - Gwynneth Thomas
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Soonkyu Chung
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Mingxia Liu
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Matthew A. Davis
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Richard G. Lee
- Cardiovascular Group, Antisense Drug Discovery, Isis Pharmaceuticals, Carlsbad, California
| | - Rosanne M. Crooke
- Cardiovascular Group, Antisense Drug Discovery, Isis Pharmaceuticals, Carlsbad, California
| | - Mark J. Graham
- Cardiovascular Group, Antisense Drug Discovery, Isis Pharmaceuticals, Carlsbad, California
| | - John S. Parks
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Dawn L. Brasaemle
- Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
| | - Michael B. Fessler
- Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina
| | - H. Alex Brown
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - J. Mark Brown
- Department of Pathology, Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina
- Corresponding author: J. Mark Brown,
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Jang JH, Lee CS, Hwang D, Ryu SH. Understanding of the roles of phospholipase D and phosphatidic acid through their binding partners. Prog Lipid Res 2011; 51:71-81. [PMID: 22212660 DOI: 10.1016/j.plipres.2011.12.003] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Phospholipase D (PLD) is a phosphatidyl choline (PC)-hydrolyzing enzyme that generates phosphatidic acid (PA), a lipid second messenger that modulates diverse intracellular signaling. Through interactions with signaling molecules, both PLD and PA can mediate a variety of cellular functions, such as, growth/proliferation, vesicle trafficking, cytoskeleton modulation, development, and morphogenesis. Therefore, systemic approaches for investigating PLD networks including interrelationship between PLD and PA and theirs binding partners, such as proteins and lipids, can enhance fundamental knowledge of roles of PLD and PA in diverse biological processes. In this review, we summarize previously reported protein-protein and protein-lipid interactions of PLD and PA and their binding partners. In addition, we describe the functional roles played by PLD and PA in these interactions, and provide PLD network that summarizes these interactions. The PLD network suggests that PLD and PA could act as a decision maker and/or as a coordinator of signal dynamics. This viewpoint provides a turning point for understanding the roles of PLD-PA as a dynamic signaling hub.
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Affiliation(s)
- Jin-Hyeok Jang
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Kyungbook 790-784, South Korea
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Zhang P, Takeuchi K, Csaki LS, Reue K. Lipin-1 phosphatidic phosphatase activity modulates phosphatidate levels to promote peroxisome proliferator-activated receptor γ (PPARγ) gene expression during adipogenesis. J Biol Chem 2011; 287:3485-94. [PMID: 22157014 DOI: 10.1074/jbc.m111.296681] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Adipose tissue plays a key role in metabolic homeostasis. Disruption of the Lpin1 gene encoding lipin-1 causes impaired adipose tissue development and function in rodents. Lipin-1 functions as a phosphatidate phosphatase (PAP) enzyme in the glycerol 3-phosphate pathway for triglyceride storage and as a transcriptional coactivator/corepressor for metabolic nuclear receptors. Previous studies established that lipin-1 is required at an early step in adipocyte differentiation for induction of the adipogenic gene transcription program, including the key regulator peroxisome proliferator-activated receptor γ (PPARγ). Here, we investigate the requirement of lipin-1 PAP versus coactivator function in the establishment of Pparg expression during adipocyte differentiation. We demonstrate that PAP activity supplied by lipin-1, lipin-2, or lipin-3, but not lipin-1 coactivator activity, can rescue Pparg gene expression and lipogenesis during adipogenesis in lipin-1-deficient preadipocytes. In adipose tissue from lipin-1-deficient mice, there is an accumulation of phosphatidate species containing a range of medium chain fatty acids and an activation of the MAPK/extracellular signal-related kinase (ERK) signaling pathway. Phosphatidate inhibits differentiation of cultured adipocytes, and this can be rescued by the expression of lipin-1 PAP activity or by inhibition of ERK signaling. These results emphasize the importance of lipid intermediates as choreographers of gene regulation during adipogenesis, and the results highlight a specific role for lipins as determinants of levels of a phosphatidic acid pool that influences Pparg expression.
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Affiliation(s)
- Peixiang Zhang
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA
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Best MD, Rowland MM, Bostic HE. Exploiting bioorthogonal chemistry to elucidate protein-lipid binding interactions and other biological roles of phospholipids. Acc Chem Res 2011; 44:686-98. [PMID: 21548554 DOI: 10.1021/ar200060y] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Lipids play critical roles in a litany of physiological and pathophysiological events, often through the regulation of protein function. These activities are generally difficult to characterize, however, because the membrane environment in which lipids operate is very complex. Moreover, lipids have a diverse range of biological functions, including the recruitment of proteins to membrane surfaces, actions as small-molecule ligands, and covalent protein modification through lipidation. Advancements in the development of bioorthogonal reactions have facilitated the study of lipid activities by providing the ability to selectively label probes bearing bioorthogonal tags within complex biological samples. In this Account, we discuss recent efforts to harness the beneficial properties of bioorthogonal labeling strategies in elucidating lipid function. Initially, we summarize strategies for the design and synthesis of lipid probes bearing bioorthogonal tags. This discussion includes issues to be considered when deciding where to incorporate the tag, particularly the presentation within a membrane environment. We then present examples of the application of these probes to the study of lipid activities, with a particular emphasis on the elucidation of protein-lipid binding interactions. One such application involves the development of lipid and membrane microarray analysis as a high-throughput platform for characterizing protein-binding interactions. Here we discuss separate strategies for binding analysis involving the immobilization of either whole liposomes or simplified isolated lipid structures. In addition, we present the different strategies that have been used to derivatize membrane surfaces via bioorthogonal reactions, either by using this chemistry to produce functionalized lipid scaffolds that can be incorporated into membranes or through direct modification of intact membrane surfaces. We then provide an overview of the development of lipid activity probes to label and identify proteins that bind to a particular lipid from complex biological samples. This process involves the strategy of activity-based proteomics, in which proteins are collectively labeled on the basis of function (in this case, ligand binding) rather than abundance. We summarize strategies for designing and applying lipid activity probes that allow for the selective labeling and characterization of protein targets. Additionally, we briefly comment on applications other than studying protein-lipid binding. These include the generation of new lipid structures with beneficial properties, labeling of tagged lipids in live cells for studies involving fluorescence imaging, elucidation of covalent protein lipidation, and identification of biosynthetic lipid intermediates. These applications illustrate the early phase of the promising field of applying bioorthogonal chemistry to the study of lipid function.
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Affiliation(s)
- Michael D. Best
- Department of Chemistry, the University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Meng M. Rowland
- Department of Chemistry, the University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Heidi E. Bostic
- Department of Chemistry, the University of Tennessee, Knoxville, Tennessee 37996, United States
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Krachler AM, Orth K. Functional characterization of the interaction between bacterial adhesin multivalent adhesion molecule 7 (MAM7) protein and its host cell ligands. J Biol Chem 2011; 286:38939-47. [PMID: 21937438 DOI: 10.1074/jbc.m111.291377] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The ability of a pathogen to rapidly form a stable interaction with the host cell surface is key to its success. Bacterial pathogens use a repertoire of virulence factors, but their efficient use relies on close contact between the host and the pathogen. We have recently identified a constitutively expressed MAM7 (multivalent adhesion molecule 7), which is widely distributed in gram-negative pathogens and enables them to establish initial contact with the host cell. Here, we describe the dissection of the MAM7 interaction with the host cell surface into two distinct binding events, involving the host protein fibronectin and the membrane phospholipid phosphatidic acid. We analyzed which domains within MAM7 and fibronectin are necessary for complex formation. We further studied phosphatidic acid binding by MAM7 using site-directed mutagenesis and liposome association assays and demonstrated that a specific distribution of basic charge on MAM7 is required for high affinity binding. Finally, we showed that fibronectin and phosphatidic acid binding to MAM7 are not mutually exclusive and that the three molecules likely assemble into a tripartite complex on the host cell surface.
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Affiliation(s)
- Anne Marie Krachler
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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Balgi AD, Diering GH, Donohue E, Lam KKY, Fonseca BD, Zimmerman C, Numata M, Roberge M. Regulation of mTORC1 signaling by pH. PLoS One 2011; 6:e21549. [PMID: 21738705 PMCID: PMC3126813 DOI: 10.1371/journal.pone.0021549] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/01/2011] [Indexed: 11/18/2022] Open
Abstract
Background Acidification of the cytoplasm and the extracellular environment is associated with many physiological and pathological conditions, such as intense exercise, hypoxia and tumourigenesis. Acidification affects important cellular functions including protein synthesis, growth, and proliferation. Many of these vital functions are controlled by mTORC1, a master regulator protein kinase that is activated by various growth-stimulating signals and inactivated by starvation conditions. Whether mTORC1 can also respond to changes in extracellular or cytoplasmic pH and play a role in limiting anabolic processes in acidic conditions is not known. Methodology/Findings We examined the effects of acidifying the extracellular medium from pH 7.4 to 6.4 on human breast carcinoma MCF-7 cells and immortalized mouse embryo fibroblasts. Decreasing the extracellular pH caused intracellular acidification and rapid, graded and reversible inhibition of mTORC1, assessed by measuring the phosphorylation of the mTORC1 substrate S6K. Fibroblasts deleted of the tuberous sclerosis complex TSC2 gene, a major negative regulator of mTORC1, were unable to inhibit mTORC1 in acidic extracellular conditions, showing that the TSC1–TSC2 complex is required for this response. Examination of the major upstream pathways converging on the TSC1–TSC2 complex showed that Akt signaling was unaffected by pH but that the Raf/MEK/ERK pathway was inhibited. Inhibition of MEK with drugs caused only modest mTORC1 inhibition, implying that other unidentified pathways also play major roles. Conclusions This study reveals a novel role for the TSC1/TSC2 complex and mTORC1 in sensing variations in ambient pH. As a common feature of low tissue perfusion, low glucose availability and high energy expenditure, acidic pH may serve as a signal for mTORC1 to downregulate energy-consuming anabolic processes such as protein synthesis as an adaptive response to metabolically stressful conditions.
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Affiliation(s)
- Aruna D. Balgi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Graham H. Diering
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Elizabeth Donohue
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Karen K. Y. Lam
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Bruno D. Fonseca
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carla Zimmerman
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Masayuki Numata
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michel Roberge
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- The Centre for Drug Research and Development, Vancouver, British Columbia, Canada
- * E-mail:
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Baljuls A, Mahr R, Schwarzenau I, Müller T, Polzien L, Hekman M, Rapp UR. Single substitution within the RKTR motif impairs kinase activity but promotes dimerization of RAF kinase. J Biol Chem 2011; 286:16491-503. [PMID: 21454547 DOI: 10.1074/jbc.m110.194167] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The serine/threonine kinase RAF is a central component of the MAPK cascade. Regulation of RAF activity is highly complex and involves recruitment to membranes and association with Ras and scaffold proteins as well as multiple phosphorylation and dephosphorylation events. Previously, we identified by molecular modeling an interaction between the N-region and the RKTR motif of the kinase domain in RAF and assigned a new function to this tetrapeptide segment. Here we found that a single substitution of each basic residue within the RKTR motif inhibited catalytic activity of all three RAF isoforms. However, the inhibition and phosphorylation pattern of C-RAF and A-RAF differed from B-RAF. Furthermore, substitution of the first arginine led to hyperphosphorylation and accumulation of A-RAF and C-RAF in plasma membrane fraction, indicating that this residue interferes with the recycling process of A-RAF and C-RAF but not B-RAF. In contrast, all RAF isoforms behave similarly with respect to the RKTR motif-dependent dimerization. The exchange of the second arginine led to exceedingly increased dimerization as long as one of the protomers was not mutated, suggesting that substitution of this residue with alanine may result in similar a structural rearrangement of the RAF kinase domain, as has been found for the C-RAF kinase domain co-crystallized with a dimerization-stabilizing RAF inhibitor. In summary, we provide evidence that each of the basic residues within the RKTR motif is indispensable for correct RAF function.
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Affiliation(s)
- Angela Baljuls
- Theodor-Boveri Institute of Bioscience, Department of Microbiology, University of Wuerzburg, Wuerzburg, Germany.
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Endocytosis of cationized ferritin in marginal cells of the stria vascularis is regulated by protein kinase, protein phosphatase, and MEK/ERK and PI3-K signaling pathways. Otol Neurotol 2011; 32:856-62. [PMID: 21358558 DOI: 10.1097/mao.0b013e318210b8ad] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS The endocytosis of cationized ferritin (CF) via a clathrin-mediated pathway is regulated by a signaling network. BACKGROUND Marginal cells showed the active endocytosis of CF via a clathrin-mediated pathway. The internalization of receptors through the clathrin-mediated pathway is an important regulatory event in signal transduction. Numerous kinases are involved in endocytosis, and each endocytic route is subjected to high-order regulation by cellular signaling mechanisms. METHODS CF was infused into the cochlear duct with phorbol 12-myristate 13 acetate, okadaic acid, staurosporin, phenylarsine oxide, PD98059, SB20580 and wortmannin. Endocytic activity was measured at 30 minutes post-infusion by transmission electron microscopy. RESULTS The endocytosis of CF was stimulated by a protein kinase C activator (phorbol 12-myristate 13 acetate) and a protein kinase A activator (8-bromoadenosine-3', 5'-cyclic monophosphate). It was inhibited by protein phosphatase inhibitors (okadaic acid and phenylarsine oxide), mitogen-activated protein kinase/extracellular signal-related kinase inhibitors (PD98059 and SB20580), and a phosphatidylinositol 3-kinase inhibitor (wortmannin). CONCLUSION Our previous study showed the endocytosis of microperoxidase to be strongly dependent on protein kinase C, protein phosphatase, extracellular signal-related kinase, and phosphatidylinositol 3-kinase signaling networks but not on protein kinase A and mitogen-activated protein kinase signaling networks. The present study indicated that the signaling cascade regulating CF's internalization differed from the cascade for microperoxidase's endocytosis.
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